A friend has a system based on a Multiplus 2 of 5000 Watts 48Volts + mppt + pylontech + cerbo GX. It was installed a year ago by a professional, and stopped working 2 weeks ago. The professional won’t come to fix it so I am trying to help.
I measured at the terminals a correct DC-in of 52 Volts, but no AC1-out.
I switched it OFF/ON with the lower right switch. Same.
I also tried from the touch screen. I can hear the relay in the MP2 doing its job so the parts seem to communicate. I tried both commands ON and also “inverter only” to restart it. Same.
The inverter stopped working when my friend turned on an electric oven. Even if it was more than 5000 watts which it isn’t, the inverter should go in overload by itself, turn off and try again 20s later, and that 3 times. Could a mosfet be burned inside, with no error message, and a solid green light “inverter on” be displayed, no other LED turned ON for an error, and no notifications?
There is indeed a msg indicating a loss of grid (AC-in), but it is normal, as my friend resiliated her contract 6 months ago to be completely off grid, and the system continued to work since then, so I don’t think it is related.
I did read the documentation and I have some experience with solar, but none with this cerbo GX stuff. Any help appreciated.
Disconnect the AC OUT and measure the voltage at the terminals.
Yes I tried that. Same.
Ah, thanks a lot Steffen. I will check that next time I go there.